I am looking to purchase a Sony TX20, and I am confused about which memory card I should get. The manual states that cards on the following list are compatible. Is there any advantage to using Memory Stick - when SD is more universally available? Is there any disadvantage in using a microsd with adapter, over a standard SD card.

Firstly - welcome to the forum
To answer your Q - the "memory stick" is exclusively a Sony device and is not used [to my knowledge] by anything other than Sony movie cameras

The SD card has come up trumps as the saying goes as the most popular memory card usable across not only cameras, but 1001 other devices as well, and it appears that soon it will be [like VHS was with video] the 'only' memory card used in the world today

Personally - I would keep to SD cards and not waste my time or money on anything else

As to Class-4 or -6 or -10 cards...
I suggest you buy good brand-name cards of at least class-6 > you will find that writing / saving time is slower than the camera's burst speed otherwise - thus whenever you're on burst, you will be waiting-waiting-waiting

I am looking to purchase a Sony TX20, and I am confused about which memory card I should get. The manual states that cards on the following list are compatible. Is there any advantage to using Memory Stick - when SD is more universally available? Is there any disadvantage in using a microsd with adapter, over a standard SD card.

Hello Cascas, either memory stick or SD will work with the camera, so it is basically your preference. The higher the class number on the SD indicates a higher minimum flow of information between the camera and the memory card. A class 4 will be fine for shooting images, and should also be good for shooting video, even in AVCHD. Obviously the higher the class the higher the flow of information. Thanks, Scott Fuentes Sony Support USA

Re: Sony TX20Hello Cascas, either memory stick or SD will work with the camera, so it is basically your preference. The higher the class number on the SD indicates a higher minimum flow of information between the camera and the memory card. A class 4 will be fine for shooting images, and should also be good for shooting video, even in AVCHD. Obviously the higher the class the higher the flow of information. Thanks, Scott Fuentes Sony Support USA

wow! i'm impressed that Sony would actually answer questions outside of their own forum or customer support. good job sony!